1. Field of the Invention
The present invention relates generally to semiconductor devices. More particularly, the present invention relates to semiconductor devices using Schottky structures.
2. Background Art
Diodes with faster reverse recovery times allow for faster switching which enables higher frequency operation. For this reason, Schottky diodes are often desirable since they provide much faster reverse recovery times compared to p-n junctions.
Previously, circuit designs using silicon (Si) based Schottky diodes have been used. However, due to the intrinsic properties of silicon, the maximum reverse bias voltage is limited by breakdown. As a result, silicon based Schottky diodes are limited to voltages of approximately 200V due to low breakdown voltages. To address this issue, the development of gallium nitride (GaN) based Schottky diodes has accelerated, since gallium nitride provides a wider band gap than silicon and supports higher breakdown voltages. Unfortunately, present designs using gallium nitride based Schottky diodes still exhibit excessive reverse leakage current, high forward voltage drop, and/or high fabrication costs.
Thus, a unique cost-effective solution resulting in high breakdown voltage and low reverse leakage current is needed to support the efficient operation of high voltage circuit designs.